Device for cultivating around a fixed object

ABSTRACT

A device for cultivating around a fixed object including a plurality of vertical cutting blades attached on a handle between outer and inner cylinders. The cutting blades are circumferentially spaced and obliquely positioned relative to the direction of rotation of the handle. Self-operating means surround each of the blades for expelling cultivated material downwardly away from the blades.

0 United States Patent [1 1 1 3,743,027 Hatfield 1 1 July 3, 1973 [54]DEVICE FOR CULTIVATING AROUND A 2,691,823 10/1954 Dombrowski 172/15 UX3,554,293 l/l971 Aman et a1. FIXED OBJECT 2,733,100 1/1956 Simonsen [76]lnventor: Cecil T. Hatfield, 1608 Micheltorena 3,127,939 4/1964 Rink$1., L05 Angeles, Calif. 90026 3,028,669 4/1962 Caskey et a1 172/13 UX[22] Filed: Apr. 12, 1971 Appl. No.: 133,285

Primary Examiner-Robert E. Pulfrey Assistant Examiner-R. T. RaderAnorneyHarris, Kiech, Russell & Kern [57] ABSTRACT A device forcultivating around a fixed object including a plurality of verticalcutting blades attached on a handle between outer and inner cylinders.The cutting blades are circumferentially spaced and obliquely positionedrelative to the direction of rotation of the handle. Self-operatingmeans surround each of the blades for expelling cultivated materialdownwardly away from the blades.

3 Claims, 10 Drawing Figures DEVICE FOR CULTIVATING AROUND A FIXEDOBJECT This invention relates generally to cultivators and moreparticularly to cultivators for use around a fixed object such as asprinkler head or the like which is in the middle portion of a lawn orgarden, or is adjacent an uncultivatable boundary such as a sidewalk,driveway, or wall.

Cultivating the ground and controlling the vegetation around a fixedobject such as a sprinkler head are perennial problems. Prior artdevices have taken the form of lawn trimmers, sod slicers and/orcombinations thereof. Many rest on the top of the sprinkler oftencausing damage to the sprinkler head. Others merely trim the grass andweeds, thereby only temporarily solving the problem. None of themprovides adequate mulching and pulverizing of the vegetation and dirttogether, or automatically deposits all such cultivated material back toits original location around the fixed object.

Accordingly, it is a general purpose of the invention to overcome theforegoing problems of the prior art devices and provide an improveddevice for semipermanently inhibiting the growth-of grass, weeds, andother vegetation around a fixed object such as a sprinkler, and forthoroughly cultivating the ground around such a fixed object withoutdamaging the object.

Another general purpose is to provide a cultivating device whichthoroughly mulches and pulverizes the vegetation and dirt around such afixed object, and then automatically deposits the resulting mixture backto its original location without leaving any residue on the object or inthe device.

Another purpose is to provide a device for cultivating around a fixedobject which utilizes a plurality of vertical cultivating blades whichare shaped, spaced, and aligned relative to each other and to thedirection of rotation to achieve optimum mulching of the vegetation anddirt surrounding the object.

A further purpose is to provide a device having the aforementionedcharacteristics which provides selfoperating means surrounding thecultivating blades for expelling cultivated material downwardly awayfrom the blades.

Another purpose is to provide a device having the aforementionedcharacteristics which provides a plurality of vertical cutting bladesattached on a handle between inner and outer cylinders so that thecultivating blades are circumferentially spaced and obliquely positionedrelative to the direction of rotation of the handle. A related purposeis to provide cutting points so that each such point on the blades isspaced a different radial distance from the vertical axis of rotation ofthe handle.

Another purpose is to provide a device having the aforementionedcharacteristics which is adaptable for use around a fixed object locatedadjacent an uncultivatable boundary. A related purpose is to provide anouter cylinder rotatablyattached to the handle and having a lateraltruncation for fitting against the boundary, with stop means forpreventing any rotation of the cultivating blades past the lateraltruncation.

Still another object is to provide a device having the aforementionedcharacteristics which is inexpensive to make, easy to disassemble forrepair or sharpening, and which can be effectively operated in a safeand simple manner around variously sized objects such as a sprinklerhead without damaging either the device or the fixed object.

Further purposes, objects, features and advantages of the invention willbe evident to those skilled in the art from the following description ofthe various embodiments and alternative forms of the invention.

In the drawings:

FIG. 1 is an isometric projection of a preferred embodiment of theinvention;

FIG. 2 is a sectional view taken along line 22 in FIG. 1 showing thepreferred embodiment of FIG. 1 with its expulsion plate partiallydepressed by the accumulation of mulched material around the cultivatingblades;

FIG. 3 is a bottom plan view of the embodiment of FIG. 1;

FIG. 4 is a bottom plan view similar to FIG. 3 showing an alternate formand positioning of cultivating blades;

FIG. 5 is a bottom plan view similar to FIG. 3 showing another alternateform and positioning of cultivating blades;

FIG. 6 shows a preferred shape of cultivating blade;

FIG. 7 shows an alternate shape of cultivating blade;

FIG. 8 shows an isometric projection of a preferred embodiment of theinvention for use against an uncultivatable boundary;

FIG. 9 is a sectional view taken along line 9-9 in FIG. 8; and

FIG. 10 is a bottom plan view of the embodiment of FIG. 8.

Generally speaking, the invention provides a handle 12 having aplurality of prepositioned cultivating blades 14 for pulverizing andmulching the vegetation 16 and dirt 18 immediately adjacent a fixedobject, such as a sprinkler head 20, to produce a cultivated material21. Self-operating expulsion means are provided such as a spring-biasedexpulsion plate 22 surrounding the cultivating blades 14, in order toautomatically expel any accumulation of the cultivated material 21 whichbuilds up around the blades 14 during rotary operation of the deviceabout the vertical axis of the handle 12.

More particularly, the illustrated embodiment of FIGS. 1, 2, and 3includes a handle 12 having a horizontal handpiece 24, a vertical axle26, an inverted U- shaped brace 28 and a horizontal disc-shaped hanger30. The handpiece 24 is fixedly attached at about its mid-point to theupper end of the vertical axle 26. The lower end of the vertical axle 26is suitably attached as by welding to the brace 28 which carries thehanger 30 on bolts 32 therebelow.

The cutting blades 14 are preferably shaped as shown in FIG. 6 havingboth sides 34 and top 36 sharpened, as by single bevel sharpening. Thesharpened cutting edges are tapered to form a single prominentlyextending cutting point 38 aligned with one of the sharpened sides 34.An alternatively shaped cutting blade 14a is shown in FIG. 7 wherein thetop 36a is sharpened, as by double beveling, and tapered to form asingle prominently extending cutting point 38a midway between theunsharpened sides 340. A plurality of cutting blades 14 are fixedlymounted in a predetermined pattern on a circular mounting plate 40 whichis removably secured by bolts 32 underneath the hanger 30. The blades 14are spaced circumferentially from each other and are positionedobliquely relative to the circular direction of rotation about thevertical axis of the handle 12.

The self-operating expulsion means for automatically expelling anyaccumulation of cultivated material 21 which may build up around theblades 14 includes the plate 22, spacing rods 42, an inverted T-shapedmember 44 and a biasing spring 46. The plate 22 is perforated with slotsconforming to the predetermined pattern of the cutting blades 14 toallow the plate to move up and down while surrounding the blades 14. Thespacing rods 42 are vertically inserted through aligned holes in theexpulsion plate 22, the mounting plate 40, the hanger 30 and theT-shaped member 44. The holes in the expulsion plate 22 are threaded toremovably mount the expulsion plate on threaded lower ends of thespacing rods 42. The upper ends of the spacing rods 42 are also threadedto carry nuts 48 securing the T shaped member 44 to the rods. Thebiasing spring 46 surrounds the stem 50 of the T-shaped member 44 andabuts against the underside of the U-shaped brace 28 while the stem ofthe Tshaped member extends through a hole in the U-shaped brace 28 intothe hollow lower end of the vertical axle 26.

The circular mounting plate 40 and the expulsion plate 22 are both sizedto fit between inner and outer cylinders 52, 54 which are mountedconcentrically under the hanger 30 and vertically aligned with thehangers inner and outer peripheries, respectively. The cylinders 52, 54are preferably sharpened to form lower cutting edges 56.

When the device is not in operation, the biasing spring 46 pushes theexpulsion plate 22 downward to the bottom of the cavity defined by theinner and outer cylinders 52,54, at which time the lower of the nuts 48contacts the hanger 30 and stops any further downward movement of theplate 22. If necessary the spacing rods 42 can be lengthened so that theexpulsion plate 22 in its normal lowered position is located below boththe' cutting points 38 of the cultivating blades 14 and also below thecutting edges 56 of the inner and outer cylinders 52, 54, thusprotecting both the supporting surface and nearby persons from beingcut.

To operate the preferred embodiment of FIGS. 1, 2, 3, and 6, thecultivating device is placed over the top of and around a sprinkler asbest shown in FIG. 2. Manual rotation of the handpiece in eitherclockwise or counterclockwise direction about the vertical axis of thehandle 12 causes the attached cutting blades 14 and inner and outercylinders 52, 54 to similarly rotate. The downward manual force exertedduring rotation easily overcomes the biasing spring 46 and causes theexpulsion plate 22 to depress exposing the vegetation and dirtimmediately surrounding the sprinkler 20 to the sharp cultivating edges34, 36 and points 38 of the cultivating blades cylinders as well as tothe sharp cutting edges 56 of the cylinders 54, 56. When the desireddepth of cultivation is achieved, downward manual pressure is stoppedand the device is lifted upwardly during which time the force of thebiasing spring 46 causes the expulsion plate 22 to return to itsnormally lowered position automatically expelling the accumulation ofcultivated material 21 back to the area surrounding the sprinkler.

The invention is not limited to the particular number and location ofcultivating blades shown. For example, FIG. 4 shows an alternatearrangement where cutting blades 14 of the types shown in FIG. 6 havecutting points 38 each of which is spaced a different radial distancefrom the axis of rotation of the handle 12, thereby producing fourseparate deep-cutting cultivation paths 58. Also, with respect to thesides of the cultivating blades 14, those sides which are not adjacentto the cylinders 52, 54 are all inclined in the same direction. In thisform, the cultivating blades 14 extend less than half the radialdistance between the inner and outer cylindres 52, 54.

In FIG. 5, another alternate arrangement provides cutting blades 14 and14a of both types shown in FIGS. 6 and 7 having cutting points 38, 38awhich are again spaced different radial distances from the axis ofrotation of the handle 12 to produce separate deep-cutting cultivationpaths 58. However, here the aforementioned sides not adjacent to thecylinders 52, 54 are both forwardly and rearwardly inclined with respectto a given circular rotation of the handle 12 about its vertical axis.In this form, the cultivating blades extend more than half the radialdistance between the inner and outer cylinders 52, 54.

It is emphasized that in each different form and embodiment, thecultivating blades 22 are positioned obliquely relative to the directionof rotation to achieve a unique improved cultivation not possible withblades merely parallel or perpendicular to the direction of rotation.

FIGS. 8, 9, and 10 show a preferred embodiment of the invention for useagainst uncultivatable boundaries.

Where possible, the identification numerals used here correspond to theidentification numerals for the same or similar parts in the embodimentof FIGS. 1, 2, and 3. Here the handle 12 includes the vertical axle 26fixedly attached through a truncated inverted T-shaped member 44a,shortened spacing rod 42a and nuts 48 to a truncated circular mountingplate 40a carrying a plurality of vertically mounted blades 14 spacedcircumferentially from each other and positioned obliquely relative tothe direction of rotation of the handle 12 about its axis.

However, the inner cylinder 52 and truncated outer cylinder 54a are notfixedly attached to the handle 12, but rather are mounted on a truncatedhanger 30a connected for rotatable movement relative to the handle 12through a shortened inverted U-shaped hanger 28a to the axle member 26.A circular slot is provided in the hanger 30a for the spacing rod 42a toride in during oscillation of the cultivating blades 14.

The end portions of the slot and the hanger 28a both stop the spacingrod 42a and its attached blades 14 from oscillating too far in eitherdirection.

Thus, it will be appreciated that by placing the device over a sprinklerso that the various truncated and shortened parts face and/or abutagainst the driveway, sidewalk, or other boundary, oscillating rotationof the bandle 12 still accomplished corresponding oscillating rotationof the cultivating blades 14 to cultivate around the sprinkler andadjacent to the boundary.

Although an exemplary embodiment and some alternative forms of theinvention have been disclosed and discussed, it will be understood thatother applications of the invention are possible, and that theemobidments and forms disclosed may be subjected to various changes,modifications, and substitutions without necessarily departing from thespirit of the invention.

I claim:

1. A device for cultivating underlying material around a fixed object ofa predetermined diameter including:

a handle rotatable in a circular direction about a vertical axis;

a mounting plate connected to and extending laterally from a lower endof said handle;

inner and outer vertical cylinders attached to said mounting plateconcentric with said vertical axis, said inner cylinder having adiameter greater than said predetermined diameter of said fixed object;

a plurality of circumferentially spaced flattened vertical cultivatingblades positioned on said mounting plate between said inner and outercylinders, each of said cultivating blades defining and lying in a planeparallel to said vertical axis and oblique relative to said circulardirection and to the radially adjacent portions of said cylinders andhaving bottom edge means for scraping the underlying material, with saidinner and outer vertical cylinders terminating in bottom cutting edgesin substantial lateral alignment with said bottom edge means of saidcultivating blades; and

a horizontal plate member between said inner and outer verticalcylinders having access slots which allow passage of said cultivatingblades respectively for cleaning any underlying material stuck betweensaid cylinders and being movable from a normally lowered positionadjacent said bottom cutting edges of said cylinders and said bottomedge means of said cultivating blades to a raised position adjacent saidmounting plate.

2. A device as defined in claim 1 wherein said cultivating blades andsaid access slots do not extend the full distance between said inner andouter cylinders, and wherein some of said bottom edge means of saidcultivating blades are spaced at different radial distances from saidvertical axis.

3. A device as defined in claim 1 in which the fixed object is adjacentan uncultivatable surface, and wherein said outer cylinder includes alaterally truncated side for positioning adjacent the uncultivatablesurface, and

said mounting plate includes means for allowing said blades to rotaterelative to said cylinders about said vertical axis including stop meansfor preventing rotation of said blades past the laterally truncated sideof said outer cylinder.

1. A device for cultivating underlying material around a fixed object ofa predetermined diameter including: a handle rotatable in a circulardirection about a vertical axis; a mounting plate connected to andextending laterally from a lower end of said handle; inner and outervertical cylinders attached to said mounting plate concentric with saidvertical axis, said inner cylinder having a diameter greater than saidpredetermined diameter of said fixed object; a plurality ofcircumferentially spaced flattened vertical cultivating bladespositioned on said mounting plate between said inner and outercylinders, each of said cultivating blades defining and lying in a planeparallel to said vertical axis and oblique relative to said circulardirection and to the radially adjacent portions of said cylinders andhaving bottom edge means for scraping the underlying material, with saidinner and outer vertical cylinders terminating in bottom cutting edgesin substantial lateral alignment with said bottom edge means of saidcultivating blades; and a horizontal plate member between said inner andouter vertical cylinders having access slots which allow passage of saidcultivating blades respectively for cleaning any underlying materialstuck between said cylinders and being movable from a normally loweredposition adjacent said bottom cutting edges of said cylinders and saidbottom edge means of said cultivating blades to a raised positionadjacent saId mounting plate.
 2. A device as defined in claim 1 whereinsaid cultivating blades and said access slots do not extend the fulldistance between said inner and outer cylinders, and wherein some ofsaid bottom edge means of said cultivating blades are spaced atdifferent radial distances from said vertical axis.
 3. A device asdefined in claim 1 in which the fixed object is adjacent anuncultivatable surface, and wherein said outer cylinder includes alaterally truncated side for positioning adjacent the uncultivatablesurface, and said mounting plate includes means for allowing said bladesto rotate relative to said cylinders about said vertical axis includingstop means for preventing rotation of said blades past the laterallytruncated side of said outer cylinder.